Ibrahim Farinloye, a spokesman for the National Emergency Management Agency (NEMA), said the collapse happened at about 2:00 pm (1300 GMT) on Tuesday on Lagos Island in the city.
“We have pulled out eight bodies from the debris of the building,” he told AFP. “One corpse was recovered yesterday (Tuesday) while seven more were recovered today (Wednesday).”
He said 15 people had been rescued from the rubble following the incident on Tuesday afternoon.
Witnesses said the tragedy happened after rains pounded the megacity of 20 million inhabitants for hours.
Resident Suleiman Olamilekan said: “I was returning from the afternoon prayers at the mosque when I heard a loud bang and the building started crumbling.”
He and others suggested a heavy telecommunication mast on the roof of the structure may have contributed to the collapse and that he had seen cracks in the building before it came down.
Building collapses are common in Nigeria’s over-crowded urban centres where people often build without government approval and in compliance to regulations.
On Saturday, a woman and her two-year-old daughter were killed when a bungalow under construction caved in after heavy rain in the Abule-Egba area of the city.
In March 2016, at least 35 people were killed when a building under construction in the upmarket Lekki area of Lagos came down after heavy rains.
Criminal charges have been filed against the head of the real estate firm and contractor for manslaughter and flouting building regulations.
The most high-profile collapse in recent years came in September 2014, when 116 people, most of them South Africans, were killed when a church guesthouse came down.
A coroner’s inquest later ruled that the addition of floors without proper planning approval was a factor.
The Synagogue Church of all Nations, run by popular evangelical preacher TB Joshua, and the contractors, are currently on trial.
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